Switch assembly



' Jan. 5 192s.

' G. S. LEDDICK SWITCH ASSEHBLY Filed July 13, 1925 2 Sheets-Sheet 1 Ifiventor': George S. LeddicK, Mf

His Attorfieg Patented Jan. 5, 1926.

ITED- STATES EPIC-7E.

GEORGE s. 'LEnnIcK, 0E SCHENECTADY NEW yonmnsstonon To GENERAL ELECTRIC COMPANY, A CORPORATION 01 NEW YORK.

SWITCH ASSEMBLY.

Application filed July 13, 1925.

To all whom it may concern.

Be it known that I, GEORGE S. LEDDIQK, a citizen of the United States, residingi-n the city ofgS'chenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Switch Assembl-ies, of which the following is a specification.

My invention relates to improvements in electric switches and in particular to details of construction and arrangement whereby the switch assembly is compact and convenient,-and nevertheless such that the labor necessary for assembly is not excessive.

Although not necessarily limited there-- to, the invention is particularly applicable to switchassemblies such .as motor starting compensators which comprise an auto-transformensw-itch mechanism or contactors for establishing the motor connections, and tie vices such as relaysand the like for controlling the switch mechanism.

- One of the featuresof the invention is the provision of a cont-actor panel pivot-ally mounted-within a casing, the panel having contactors thereonsmounted back to back on opposite-sides of thepanel, the contactor or contactors on one sideof the panel facing the front opening of the casing and the contactor or contactors onthe other side of the panelfacing the near conduit outlet opening of the casing, WherehyLby tilting the panel toward the front opening the contactor or contactors on the rear side of the panel are readily accessible for inspection.

Other features of the invention will be pointed out particularly as the specification proceeds, and reference is had to the accompanying drawings showingan. embodiment of the invention, Fig. 1 ofwhich is a perspective view of the switch assembly with a portion .of the casing removed for the purpose of explaining the features of construction andlarrangement Fig. 2 is. a detail for the purpose of showing the mechanical intel-locking arrangement between the contactors on opposite sides of the .contaotor panel, and Fig.3 isaside viewwof thearrangement. of Fig. .1 with the .end portion of the casi-xng removed.

Referring. to the drawings, the switch assembly is enclosed. within a casing 10 which is providedwith a rear opening which cooperates with the conduitoutletbox 11 so as=to form a completely enclosed receptacle Serial No. 43,209.

for theswitch assembly and the conductors leading therefrom. The panel 12, of any suitable insulating material, is pivotally mounted within the casing, the lower edge of the panel being provided at each end thereof with a forked supporting member 13 which forms an open pivotal hearingfor the panel on the supporting rod 14 which extendstransversely of the casing. This supportmgrod is secured in the side walls of the casing, and the arrangement is such that byreason of the open pinota-lebearhig of the contactor panel, this panelmaybe very readily assembled within the casing and also he very readily removed for the purpose. of inspection and repair. The contactor panel has :a three pole electromagnetic switch or .contactor 15.n1onntedou the rear of the panel, facing the rear conduit outlet opening, and another contactor 16 on the front of the panel, facing thef-ront opening of the casing. These contactors are mounted backto back on. opposite sides. of the panel. thereby making-the moSt effective use of the contactor. p anel and minimizing. very greatly, the total space takenlup by the panel and the contactors.

These contaotors are of any suitable construction, and I have shown a well known type of contactor employing each an operating rod 17 carrying a plurality of movable contacts (not shown) which cooperate within the arc chutes 18 with corresponding stationary contacts. The operating rods are each operated by means .of a separate armature 19 of an electromagnetic ope-rating means having a winding 20 on the magnetic structure thereof. It is believed that a detailed description. of tfhisparticular type of electromagnetic switch or contactor is unnecessary to an understandingof.the invention, gsince-the type which I have shown a well known'form and, furthermore, the invention is not necessarily limited to any particular type of electromagnetic switch or contactor. The contactors are interlocked so as to. prevent the one contactor from closing while the other contactor is closed, vand this feature of the invention is illustrated clearly in Fig. 2, in which the mechanical interlock 21 cooperates with the operating shaftsv 17 .of the two-contactors :50 as to permitei-ther contactor to close, provided the other contactor isopen, but which prevents the closing of either .contactor provided the other contactor is closed. This mechanical interlock extends through the panel as shown, thereby also economizing in the space taken by this part of the mechanism.

The contactor panel is normally in the position indicated in Fig. 3, in which the panel is held in the vertical position by means of the catches 22 which cooperate with the cross rod 23 having its end secured in the side walls of the casing 10. It will be observed that in Fig. 3 the contactor 16 is shown in the attracted or closed position and the contactor 15 is shown in the open or unattracted position. As applied to a starting compensator, the contactor 16 may be em ployed as the starting switch for connecting a motor to a source of supply (not shown) through the reduced voltage taps of the auto-transformer 24. The contactor 15 will then be employed to connect the motor directly to the source of supply after the motor has started on the reduced voltage tap of the auto-transformer. A system of motor control employing the auto-transformer, the switch mechanism and the relays employed in the switch assembly of my invention. has not been shown for the reason that such systems of motor control are old and well understood by those skilled in the art, and for the further reason that the motor control system is not of the essence of my invention. It will be understood in reading the drawings that in Fig. 3 the switch mechanism is in such a position that the motor starting connections have been established, and that in the normal position of the contactors, the contactor 16 will be in its biased or open position, the same as the contactor 15. When the contactors 16 and 15 are in their respective open positions, the controlled motor (not shown) will be disconnected from the source ofsupply (not shown).

The front of the casing 10 is provided with 'a pivotally mounted cover or door 25,'which is held in the closed position 111 any suitable manner. I have indicated the locking mechanism 26 for this purpose, but the invention is not limited to any particular type of look- 'ing mechanism. It will be observed that the contactor 16' is readily accessible from the front or top of the casing by opening the door 25, but that the contactor 15 in the rear of the panel 12 is not accessible with the contactor panel in its vertical position as shown in 3. However, by reason of the fact that the contactor panel is pivotally mounted within the casing, the contactor 15 in the rear of the panel may be readily inspected from the front or the top of the casing by backing oil the catches 22 and releasing these catches from the rod 23, thus permitting the panel 12 to be tilted toward the front of the casing. The contactor panel is shown in this position in Fig. 1, and it will be observed that the catch 27 is provided for engaging the rod 23 and thereby securely holding this panel in the proper position within the casing for the inspection of the rear contactor 15 from the front of the casing.

it will also be noted that the terminal board 28 is secured on the rear wall of the casing 10 adjacent the conduit outlet opening of the casing, thereby forming a very convenient assembly of the apparatus and further providing that this terminal board is normally hidden from view so as to prevent tampering with the same by unauthorized persons. Since the connections to this terminal board are ordinarily left as originally made, it is desirable that this terminal board be out of view'ordinarily, but nevertheless be readily accessible to authorized persons in case it is desired to remove the connections. It can readily be seen that the terminal board is readily accessible from the front or top of the casing when the contactor panel is tilted toward the front of the casing as shown in Fig. 1. One of the advantages of the construction and arrangement is that the conduit outlet box 11 may be installed, the cables 29 brought in and permanently connected to the terminal board 28 before the rest of the switch mechanism is installed. This is advantageous since the electricians wiring a building are able to finish their wiring completely to the compensator, so that the compensator may be installed at any later time.

The enclosing case is supported in position by means of the conduit outlet box 11 which is secured in any suitable manner to a frame work or the walls of a building or the like, and also by means of the supporting straps 30 which are secured to the lower end of the casing. The auto-transformer 24 is secured within the casing to the rear wall thereof and beneath and to the rear of the contactor panel 12. This auto-transformer is secured to the casing in any suitable manner and I have indicated the straps 31 for this purpose. The auto-transformer is also supported by the bracket 31 and the bracket 31 supports the auto-transformer in case the straps 31 become loosened and the casing is turned upside down during shipment. The autotransformer is a part of the apparatus which ordinarily needs no inspection during the ordinary life of the compensator, so that this arrangement of the parts places the autotransformer in such a position that it is quite unlikely that an operator would ever come in engagement therewith. The starting and running contactors are controlled by means of relays which are mounted on the support 32, which has its ends secured to the side walls of the casing 10 and is secured in position within the casing beneath and to the front of the contactor panel 12. This support provides a stiffening member for the casing as well as a support for the thermal protective relay and the time element relay =34.

In general it may besai d that the relay 33 may 'beof any suitabletypefor theprotection of themotor-against overheating. I have show-n tl ierelay as of the type disclosed and claimedin the patent to-Chester I. PI-all, No. 1,521,646, dated February 2 1,

1 925 This thermal relay is provided with a reset mechanism to which the pull cord 35 is attachedso that when the relay operates to openthe-inotor controlling contactors in responseto-an overload in the usual man ner, the relay may be reset without opening the casing bymerely pulling on the cord 35. The time-elemen-trelay 3etis provided for introducing a definite time interval bet-ween the closing ofthestarting' cont-actor 16 and the closing of the running contactor 15. My invention 'is not limited to any specific form of time .e lement relay, and I have. shown somewhat in outline the time element relay fully disclosed and claimed in the patent to Ghester 1. Hall, No. 1383,4323, dated February--12, 1924s This relay is provided with an enclosing cover '36 to protect the various parts of the relay from dust and from injury due to other causes. This relay is capable of adjustment over a rather large range, as is set forth inthe said Chester I. Hall patent, and after the relay has been set for the particular installation, the setting thereof ,will ordinarily not need to be changed as long as the-controlled motor is performing the same Work. However, it will be observed that in case it is desired to adjust either the thermal-protective relay 33 or the time element relay 34, this may be readily donewithout disturbing any of the apparatus within the casing after the front door 25 of the casing has been opened.

It will be apparent from the foregoing that my switch assembly makes possible the enclosureof a comparatively large amount of apparatus by means of a relatively small enclosing casing, since the space within the casing is used to-the greatest advantage. Furthermorefit will be seen that all of the partsofythc apparatus which ordinarily ever need inspection a-re readily accessible for that purpose. The starting contactor 16, the controlling relays 33 and 34 are readily accessible, and the running contactor 15 on the rear of the panel and the terminal board 28 adjacent the rear conduit outlet opening are readily accessible by merely tilting the panel about its pivotal support within the casing. It will also be observed that the arrangement has features of advantage from the standpoint of assembly. In other words, the contactor panel may be assembled as a unit with the proper electrical conductors leading therefrom, and this panel may be very readily assembled within the casing by mounting the panel on the supporting rod l i. l Vith the panel tilted forward as shown in Fig. 1, the connections tothe rear terminal board may be very readily and conveniently made. It will also be observed that the contactor panel may be very readily reiuovedfron'i the casing for repairs by simplytilting the panel to the position as shown inF-ig. 1, removing the connections between the panel and the terminal board and lifting the panel out of the casing. This is of advantage, since the contactors are the parts of the assembly which get the most severe service and which ordinarily need most frequent inspection and repair. The top cover of the casing is readily removed by loosening the catch and unhooking this cover from the pins 37, thus permitting of ready inspection of the switch assembly from the top of the casing.

hat- I claim as new and desire to secure by Letters Patent of the United States, is:

1. A switch assembly comprising a casing, a contactor panel mounted within said casing and having a pivotal bearing with respect thereto, the said panel having two electromagnetic switches mounted back to back on opposite sides of said panel.

2. A switch assembly comprising a casing, a contactor panel mounted within said casing and having an open pivotal bearing with respect thereto, the said panel having two contactors mounted back to back on opposite sides of said panel, whereby the contactors and panel take up a minimum of the space within the casing, the panel with the contactors thereon is readily assembled within the casing and readily removed therefrom, and the contactor-s may be readily inspected by tilting the panel about its support.

3. A switch assembly comprising a casing, a contactor panel pivotally mounted within said casing, the said panel having two contactors mounted back to back on opposite sides of said panel, and a mechanical interlock extendingthrough'the panel and cooperating with said contactors for maintaining one of the contactors open while the other is closed.

l. A switch assembly comprising a pivotally mounted support, an electromagnetic switch mounted on each side of said sup ort, a casing for said switches having a front opening and a rear conduit outlet opening, the said support being mounted within the casing so that with the support in its normal position one of said switches faces the front opening of the casing and the second of said switches faces the rear conduit outlet opening of the casing, the second of said switches being accessible for inspection by tilting the said support toward the front opening.

5. A switch assembly comprising a casing having a rear conduit outlet opening, a terminal board mounted within the casing adjacent said opening, a switch panel pivotally mounted within said casing in front of said opening, a contactor mountedon the front of said panel facing the front of the casing and acontactor mounted on the rear of the panel facing the said opening, the said contactor mounted on the rear of the panel being accessible by tilting the said panel about its pivot toward the front of the casing.

6.-A switch assembly comprising a casing having a rear conduit outlet opening, a switch panel pivotally mounted within said casing in front of said opening, the pivotal mounting of the panel being arranged to permit ready removal of the panel from the casing, a contactor mounted on the front of said panel facing the front of the casing and a cont-actor mounted on the rear of the panel facing the said opening, the said contactor mounted on the rear of the panel being accessible by tilting-the said panel about its pivot toward the front of the easing, and a mechanical interlock extending through the said panel for preventing either of said contactors from closing while the other contactor is closed.

7. A switch assembly comprising a casing having a front opening and a rear conduit outlet opening, a supporting rod extending transversely of the casing, a switch panel having an open pivotal bearing on said rod so that the panel is supported by the rod and is readily removable from the casing, a contactor mounted on the front of said panel facing the front opening of the casing and a contactor mounted on the rear of said panel facing the said conduit outlet opening of the casing, the said contactor on the rear of the panel being readily accessible by tilting the said panel toward the front of the casing.

8. A motor starting compensator comprising a casing having a conduit outlet opening at the upper rear end thereof, a terminal board mounted withi'n'the casing adjacent the said opening, a contactor panel pivotally mounted within said casing in front of said opening, starting and running contactors mounted on said panel, the said contactors being mounted on opposite sides of said panel so that with the panel in normal posi-' tion within the casing the contactor on the front of said panel is readily accessible from the front of the casing and the contactor on therear of the panel is not readily, accessible from the front of the casing, the said contactor on the rear of the panel being readily accessible from the front of the casing by swinging said panel about its pivotalsupport toward the front of the casing, an autotransformer mounted within said casing beneath and to the rear of said panel, and a plurality of controlling relays mounted within said casing beneath and to the front of said panel independently of said panel and auto-transformer.

9. A motor starting compensator comprising a casing having a conduit outlet opening at the upper rear end thereof, a terminal board mounted within said casing on the rear wall thereof'adjacent the said opening, an auto-transformer mounted on the rear wall of the casing below said terminal board, a supporting rod extending transversely of the casing intermediate the front and rear walls of the casing, a switch panel having an open pivotal bearing on said rod so that the panel is supported by the rod and is readily removable from the casing, starting and running eontactors mounted on said panel, the said contactors being mounted on opposite sides of said panel so that when the panel is in normal position within the casing the contactor on the front of the panel is readily accessible from the front of the easing and the contactor on the rear of the panel is readily accessible from the front of the casing by swinging the panel about its pivotal support toward the front of the casing, a mechanical interlock extending through said panel for n'eventing either of said contactors from being closed while the other of said contactors is closed, and a plu- 'ality of controlling relays for said contactors mounted within said casing beneath and to the front of said panel.

In witness whereof, I have hereunto set my hand this 10th day of July, 1925.

GEORGE S. LEDDICK. 

